The government will dispatch up to 140,000 Self-Defense Forces personnel, police officers and firefighters from across Japan to the Tokyo metropolitan area in the event of a magnitude-7 earthquake occurring directly beneath the area, the draft of a government emergency response plan shows.

According to the plan, obtained by Kyodo News on Tuesday and expected to be released later this month, advance teams will be dispatched immediately after the disaster without waiting for requests from municipalities in affected areas.

Other teams will try to reach Tokyo within 24 hours by the quickest route available via land, sea or air, and begin full-scale rescue activities as soon as possible.

The draft plan clarifies disaster response activities for the 72 hours after a disaster, which experts say is the crucial period for finding survivors.

After 72 hours, the government will consider dispatching additional personnel from less-damaged regions, and send a maximum of 110,000 SDF members, 16,000 firefighters and 14,000 police officers.

The plan revises a similar plan drawn up in 2008. The government has expanded the scale of its disaster relief operation based on an estimate that a magnitude-7.3 earthquake could occur beneath the southern Tokyo area, and under the worst case scenario, leave 23,000 people dead and destroy — either through shaking or subsequent fires — 610,000 buildings.

The government’s quake panel came up with the estimate in 2013 after the 2011 massive earthquake and tsunami that ravaged northeastern Japan. The panel has said there is a 70 percent chance that such a quake will take place beneath Tokyo in the next 30 years.